In honor of this very important holiday, this old grammar salt will teach you the difference between presume vs. assume,so that you always look and sound like true buccaneer. Yo ho ho.

According to Merriam Webster:

Assume: to take as granted or true

Presume: to expect or assume especially with confidence

The dictionary tells us that these two words are basically synonymous, except that presume is used more authoritatively than assume. AR! But let's give these definitions some heave ho and consider them in usage. For example:

When the lad saw the man with a peg leg and a parrot on his shoulder, he said "I presume you're a pirate."

Many pirates assume they will be shark bait someday, which is why they are usually three sheets to the wind.

The doctor presumed the sickly looking pirate had scurvy after being on board a ship for over three years with nothing but biscuits to eat.

The captain is so sure the white whale exists, he assumes everyone else believes it exists too.

Batten down the hatches now, because a storm is brewing -- this bucko disagrees with Merriam Webster's landlubber definitions of presume and assume. From the crow's nest, it would appear that assume is really the word that is often said with more confidence, rather than presume (which is the exact opposite of Merriam Webster's definition). Well blow me down!

Look at this example again:

When the lad saw the man with a peg leg and a parrot on his shoulder, he said "I presume you're a pirate."

In this case, presume suggests that the lad is going out on a limb by assuming the man with a peg leg and a parrot is a pirate -- maybe he's not really a seadog at all. The word presume implies that there is an expectation for clarification or more information that might change the conclusion. Savvy?

On the other hand, the word assume seems like it is indeed said with confidence, since it doesn't seem like the speaker cares if the conclusion is right or wrong:

Many pirates assume they will be shark bait someday, which is why they are usually three sheets to the wind.

That's why the saying goes "Don't assume -- it makes an 'ass' out of 'u' and 'me.'" Because assume comes to a conclusion based on the current information provided regardless.